Fiber optic cables are the backbone of optical fiber telecommunication networks. Multiple fiber optic cables are often included in a “harness,” with the individual cables broken out at the end of the harness to connect to different locations.
Fiber optic cables used in harnesses can be classified into three main groups: tight-buffered cables, loose-tube cables, and single-tube cables. Tight-buffered cables are designed for indoor applications, have very good flexibility, and can be bent with a relatively small bend radius. One example tight-buffered cable uses a 125 μm diameter fiber with a low-friction acrylate layer that extends to an outside diameter of 250 μm. Next, a polymer buffer layer is added to the outside diameter of the low friction layer to form a protective cover that has an outside diameter of 900 μm.
Harness manufacturing using tight-buffered cables typically requires removing a 2 m section (length) of the protective cover without damaging or stressing the underlying acrylate layer or the glass fiber. Such damage can lead to optical transmission degradation (i.e., attenuation of the transmitted optical signal) or fiber breakage, either of which results in the harness failing to meet the required tolerances and having to be scrapped. More generally, fiber cable manufacturing and fiber cable installation requires stripping sections of the protective cover from the underlying elements, which include, by definition, at least one optical fiber, but may also include other elements such as buffer tubes, strength elements, etc., depending on the particular type of cable.
Presently, mechanical fiber optic cable stripping tools are predominantly used to strip sections of fiber optic cables. However, these stripping tools have significant drawbacks. One drawback is that they rely upon the skill and experience of the craftsperson to cut through the protective cover without damaging or stressing the elements within the cable, especially the one or more optical fibers. One of the most widely used stripping tools is limited to a 300 mm strip length, thereby requiring the craftsperson to make numerous circumferential cuts and strips to reach greater lengths, such as the aforementioned 2 m length. The need to make numerous cuts multiplies the risk of an error that can damage the cable. Another commonly used stripping tool employs a razor blade that needs proper adjustment and frequent replacement. Complicating matters further, damage to the underlying elements in the cable, such as an acrylate layer or the glass optical fiber, is not always visible to the naked eye and only becomes apparent later in the manufacturing process, or when the harness is deployed in the field.